Bruce Paddock was taken into custody moments ago in North Hollywood, CA at an assisted living home.

Law enforcement sources tell us … cops were tipped that there was child porn on his computer and they got a search warrant. Our sources say the investigation began before his brother, Stephen, shot up the Vegas music festival earlier this month.

Our sources say before the shooting cops were trying to locate Bruce without success, but after his brother committed his heinous act a tip came in Bruce was living at an assisted living facility.